A free electron of $2.6 \mathrm{eV}$ energy collides with a ${\mathrm{H}}^{+}$ ion. This results in the formation of a hydrogen atom in the first excited state and a photon is released. Find the frequency of the emitted photon. $\left(h=6.6\times {10}^{-34} \mathrm{J} \mathrm{s}\right)$

• A

  $9.0\times {10}^{27} \mathrm{MHz}$
• Correct answer
  B

  $1.45\times {10}^9 \mathrm{MHz}$
• C

  $0.19\times {10}^{15} \mathrm{MHz}$
• D

  $1.45\times {10}^{16} \mathrm{MHz}$

Hence, the correct answer is option: 'B'.